Marker buoy for air or surface craft



July '10, 1951 B. c. GRIEB MARKER BUOY FOR AIR OR SURFACE CRAFT 2Sheets-Sheet 1 Filed Feb. 10, 1947 INVENTOR ATTORNEY July 10, 1951 B. c.GRIEB MARKER BUOY FOR AIR OR SURFACE CRAFT 2 Sheets-Sheet 2 Filed Feb.10, 1947 INVENTOR BY (m ATTORNEY Patentecl July 10, 1951 MARKER BUOY FORAIR OR SURFACE CRAFT Benjamin Curtis Grieb, Chestnut Hill, Pa., assignorto Air-Shields, Inc., Hatboro, Pa., a corporation of DelawareApplication February 10, 1947, Serial No. 727,487

11 Claims. 1

This invention relates to equipment for marking the location of craftwhich may have sunk below the surface of the water. It is particularlyapplicable to surface vessels or aircraft.

It is an object of the present invention to provide an improved type ofmarker buoy which is automatic in operation and which may be applied toa surface vessel or aircraft.

In case of accident which causes the craft to sink, it is desirable tohave the location marked so that it may be readily found and salvageoperations may be undertaken with a minimum loss of time.

It is an object of the present invention to provide a buoy assemblywhich is mounted in position in a cradle suitable for attachment to theaircraft or other structure by means of a simple fastening such as bybolts or screws. The present construction contemplates assembly of themarker buoy in the cradle at the point of manufacture which it may bedone by mechanics familiar with the construction and operation of theautomatic latches and other parts of the equipment. The device may thenbe inspected for proper mechanical relationship of parts. The operationsof setting and adjusting these parts in the field are thus eliminatedand the installation of the marker buoy involves merely the mechanicalattachment of the unit to the craft.

Another object of the invention is the provision of an improved latchconstruction and improved operating mechanism therefor.

A further object is the provision of improved apparatus for thefloatation chamber and its association with the operation of the latchmechanism. In order to prevent operation of the release mechanism at anytime except under the action of hydrostatic pressure upon submergence,the floatation chamber is provided With a connection to the pistonchamber of the latch mechanism. Improved sealing apparatus is used tomaintain the air in the two chambers at normal atmospheric pressure.Thus when the buoy mechanism is used in connection with an aircraft,normal sea level pressures are maintained in the system even at highaltitudes. This avoids the possibility of actuation of the latch uponrapid descent from high altitudes. Such problems have been inherent inpreviously proposed constructions where leakage of the sea levelpressure permitted reduced pressure in the system at altitude so thatupon rapid descent the increase in atmospheric pressure could causeundesired operation of the latch mechanism. With the construction of thepresent invention such opera- 2 tion is prevented by accurate control ofthe release due to an increase above atmospheric such as occurs uponsubmergence. The pressure of a few feet of water is sufiicient to causeoperation of the latch.

Another object of the present invention is the construction whichprovides for improved assembly operations and includes a light framework upon which the various parts of the apparatus are mounted prior toinserting in the inclosure case.

A further object of the invention is the provision of improved apparatusfor operating the light switch after release of the marker unit from thecraft.

A still further object of the invention is to improve the constructionand assembly of the various items of equipment associated with themarker buoy. One aspect of this improved assembly is the construction ofthe marker dye substance into a cylindrical unit having a hollow spaceWithin it to house the batteries used for supplying the indicatorlights. This arrangement provides for greater compactness.

How the foregoing and other objects and advantages of this invention areattained will be evident from the description of the drawings in which--Figure 1 illustrates a buoy according to the present invention and itsmethod of operation in connection with a sunken aircraft.

Figure 2 is an enlarged view showing the assembled buoy mounted in itscradle ready for installation.

Figure 3 is a longitudinal sectional View taken in the direction of thearrows 33 in Figure 2.

Figure 4 is an enlarged view of the release latch and its actuatingmechanism.

Figure 5 is a sectional View taken in the direction of the arrows 55 inFigure 4.

Figure 6 is a sectional view of .the special electrical switch used withthe buoy apparatus, drawn to an enlarged scale.

Referring to the drawings, it will be seen that the buoy unit ii] isadapted for attachment to an aircraft such as indicated at i I. In theparticular arrangement illustrated, the buoy has been mounted on theupper portion of the fuselage of the craft in such a manner that it isfree to release'and float to the surface in case the aircraft becomessubmerged after a forced landing on water. The location of the buoyallows it to separate itself from the aircraft without danger ofbecoming entangled with other parts of the ship. The buoy in releasedposition floating on the surface is illustrated at led in dottedoutline, the buoy being attached to the sunken craft by line l2.

The detail construction with the various improvements in the presentbuoyunit are more clearly illustrated in Figs. 2 to 6. In Figure 2 itwill be observed that the buoy unit It is supported in a cradle [3 whichis attached to the aircraft by means of bolts l4. Polts M are embeddedin blocks l5 which form part of the cradle 13 and provide a simple andrapid method of attachment of the unit to the craft. The unit It? isretained in the cradle l3 by means of a pair of cylindrical latches l8which project through holes 5? in the cradle I3. The details foroperating this latch mechanism will be described later.

The buoy unit I 9 is constructed with a large cylindrical chamber 23comprising a large portion of the volume of the buoy. This chamber isprovided with walls having sufilcient strength to withstand aconsiderable variation in the external pressure. At the upper end of thebuoy there is a small water tight chamber having a transparent dome 19as a cover. Located in this upper chamber is a light bulb 2i) and aspecially shaped mercury switch 2!. The location of the buoyancy chamberI8 is such that the buoy tends to float in an upright position with theupper end projecting from the water. The action of swinging to theupright position causes operation of the mercury switch 2| to completethe electrical circuit and thus light the bulb 29. Batteries 22 providethe electrical energy for illumination of the bulb 28. These batteriesare located at the lower end of the buoy unit in order to provide a lowcenter of gravity for the unit. An electrical conductor 23 connects onepole of the battery unit to the mercury switch 2!. The bulb has one ofits contacts grounded to the frame of the unit while the other pole ofthe battery unit 22 is grounded to the frame by means of spring 24thereby completing theelectrical circuit.

Immediately below the upper dome chamber there is located a cylindricalroll of fine line illusis indicated in Figures 1, 2 and 3 by the numeralI2, is attached to the cradle l3. With this arrangement the line l2permits the buoy to rise freely to the surface without danger of foulingon either the buoy or the craft. It will be noted that since the roll ofline is housed in the buoy there is no motion of the line at the craftas it extends to permit the buoy to reach the surface.

Thus thedanger of a moving line snagging on parts of the sunken craft oron other obstructions under the surface is obviated.

It will be seen that when the buoy reaches the surface the light 20 willbe illuminated and increase the visibility of the buoy to assist thesearchers to locate the sunken craft. The light will be particularlyeifective at night. To make the detection of the buoy during daytimeeasier, a soluble dye is used which produces a bright color on thesurface of the water in the locality of the buoy. In the present buoyunit this marking dye is carried in the form of a cylindrical member 26which is preferably located in the lower end of the buoy unit and in thepresent disclosure forms a hollow housing inside which the batteries 22are located. Upon immersion of the craft and release of the buoy the dyein the cylindrical unit 26 gradually dissolves and produces thedistinctive marking in the water which persists for a considerablelength of time. Under favorable conditions the dye may be effective forseveral days.

The latch operating mechanism is located in the buoy in the regionbetween the buoyancy chamber l8 and the dye unit 23. The details of thismechanism are most clearly illustrated in Figures 4 and 5-. Here it willbe seen that each cylindrical latch part I6 is connected to an enlargedportion 21 having an arcuate shape adapted to roll on the inner surfaceof the buoy casing 28. A separate cylindrical rod 29 is adapted totelescope into a suitable opening 30 in the latch member 2'7. Attachedto the cylindrical rod 29 is an enlarged portion 3| having a rectangularshape which is adapted to cooperate with the corresponding part from theopposite latch as is clearly illustrated in Figure 5. A pivot '32 isused to connect members 3| together and at the same time attach them toa fork part 33 which is provided. with a shank having an internal threadSt. A piston device is attached to the fork 33 for actuation of thelatch unit.

Associated with the cylinder device is a cylindrical chamber having wall35 and diaphragm 36. The piston member 37 is mounted in the cylinder andis connected by means of rod 38 to the fork 33, there being a malethread provided on piston rod 38 to cooperate with the internal thread34. A cylindrical projection 39 is provided around the piston rod 38 atthe point where it projects through the diaphragm 35. At the oppositeend of the cylinder 35 is a diaphragm 413 having perforations 41 toallow ingress of water upon submergence. A flexible diaphragm member 42is provided to cover the piston and the open end of the cylinder.Diaphragm 52 assures absolute tightness of the chamber while at the sametime allowing free movement of the piston 3'! under the action ofpressure which may develop'through perforations ii against the outerside of the pisten 37. A tight tubular seal 13 which may be of flexiblerubber or the like is provided between the cylindrical extension 39 andthe shank of the fork 33. This seal prevents the possibility of leakagepast the piston rod. A tube 44 is provided to interconnect the buoyancychamber l8 with the piston chamber 35. The purpose of thisinterconnection which is leakproof will be described later in connectionwith the description of the latch operation.

It will be noted that a spring 45 has been provided between the latchmember 21 and the rod member 3!. This spring tends to urge the latchinto extended position so that the cylindrical members 13 projectthrough the openings in the buoy casing 28. The spring 45 howeverpermits the latch members to be depressed inwardly by hand for thepurpose of inserting the buoy unit into the cradle i3. When the buoy isin position in the cradle l3, the latch cylinders 16 are urged under theinfluence of spring 45 through openings I? to retain the buoy in thecradle.

The cylindrical shape of the present unit provides a simple and compactarrangement for the manufacture and assembly of the various parts makingup the unit. In order to further simplify the manufacture and assemblyof the unit the various components are assembled as separate units.Various bulkheads or diaphragms are provided for the support of thesub-assemblies as indicated clearly in Figure 3 by the diaphragm 46 -istransmitted to the latch projections 15.

on which the light and switch are mounted, the diaphragms 41 and 41asupporting the anchor line unit, the bulkheads 48 and 48a supporting thebuoyancy chamber, the bulkheads 3'6 and 4d supporting the piston unitand the bulkheads l9 and 49a supporting the dye and battery unit. Allthese diaphragms or bulkheads are assembled in sequence with the unitswhich they support upon three light rods which constitute a supportingframework. These rods or longerons are clearly illustrated in Figures 3,4 and 5 where the side longeron rods 50 and the top longeron rod 5| maybe observed. It should be noted that these bulkheads are relativelyloose fitting both around their periphery and around the openingsthrough which rods 50 and 5| pass.

After assembling the various components which go to make up the internalparts of the buoy on the framework, the complete component assembly isinserted into the cylindrical casing 23. dome-shaped end portions [9 and52 are then screwed into positions to complete the assembly. Certain ofthe latch parts including springs 45 and members 2'1 are inserted intoposition after the cylindrical casing 28 is applied. -To permit assemblyof these parts a comparatively large opening 53 (see Figure 4) issupplied through which these latch parts may be inserted. Once the latchparts are slipped into position so that the parts l'S project through inhousing 28, the springs 45 retain the parts in proper relative position.To mount the buoy unit in the cradle 13 the cylindrical latch projectingparts it are depressed manually and the unit placed in proper relativeposition when the latch terminal IE will snap into holes H in cradle I3to retain the buoy in the cradle. The end of the attachment line l2,which projects through a suitable hole in casing 23, is attached to thecradle in the fashion shown in Figures 2 and 3 just before the buoy islatched to the cradle.

Operation of the buoy is automatic. Upon submergence of the craft evento a few feet in depth, the hydraulic pressure developed is considerablyabove the atmospheric pressure of the gas enclosed in the buoyancychamber and the piston chamber. Water may enter the buoy through thelarge opening 53 and finds its way to'the piston chamber and dye chamberthrough the supporting bulkheads which are not watertight. Thehydrostatic pressure therefore causes motion of the piston toward thebottom 36 of the cylinder. This motion is transmitted by the piston rod38 to the fork 33 and thereby causes tilting of the toggle members 2'!and in rolling on their arcuate surfaces a withdrawing motion When thetoggle members 3! have reached a position such as indicated in dottedoutline in Figure 4 the latch it will be withdrawn from the hole I! incradle 13 thus freeing the marker buoy from the craft and permitting itto rise to the surface.

The line 12 anchors the buoy to the sunken craft and the buoy is thusprevented from drifting away. Assoon as released the buoy assumes anupright position and the circuit is completed through the medium of thespecial mercury switch 2| thus causing illumination of the light 20. Atthe same time the action of the water upon the dyecauses a coloring ofthe water in the region of the buoy, thus making the location of thebuoy visible from a great distance.

It should be noted that connection of the cylinder chamber under thepiston 3'! by means of tube 44 to the buoyancy chamber provides a The I6 large volume of air at sea level pressure. Upon increase of pressureto a point above this nor.- mal sea level pressure the piston movesdownwardly in the cylinder. No appreciable resisting pressure is builtup in the cylinder chamher due to compression of the air under thepiston since this is connected with the volume of air in the buoyancychamber. Thus the operation of the latch can be accurately controlled tooperate in response to a desired pressure on the piston. This isgenerally arranged for actuation under a hydrostatic pressure of 3 or4feet of water. It will be further noted that release of the latches IEto disconnect the buoy from, the craft is controlled positively ratherthan by means of springs. Thus in case :increased friction or the likecauses greater resistance to the release of the latch thenconteinplated, the latches will be released at a slightly greater "depthby the increased pressure on the :piston which will overcome anydiscrepancy in the latch mechanism.

An important aspect of the construction of the present mechanism is itsparticular ,method of control of the latch release. In some previoustypes of mechanism where leakage could occur into the piston chamberunder the cylinder '3'! a reduced pressure would occur in the cylinderchamber when an aircraft was fiown at high altitudes for considerableperiods. With the present arrangement in which there are positive sealsprotecting the operating cylinder chamber, such a cylindrical seal 43around the piston rod exit, and diaphragm seal 12 on the pressure sideof the piston, reduced air pressure at altitude cannot affect thepressure in the cylinder chamber. The air in the operating cylinderremains at the normal seal level pressure. Therefore a sudden descent ofthe aircraft such as in a dive cannot build up a higher pressure on theouter side of the piston than on the inner side. It will be evident thatinadequate sealing of the operating cylinder could cause inadvertentoperation-of the latch mechanism and undesired release of the buoy.

The light operating switch shown in Figure 6 is made in a special shapehaving a cylindrical depression in the bottom of which the contaets forcompletion of the electric circuit are located. The axis of the switchis located parallel to the longitudinal axis of the buoy mechanism. Anenlarged circular or globular part of the switch is illustrated at 55.With the buoy in horizontal position as illustrated in Figure .3

z the mercury 51 in the switch will lie at the lowest point of thecircumference of the enlarged portion 56. A slight hump 58 is providedaround the entrance to the cylindrical section 5.5 to prevent normalmovements of the buoy or craft from causing the mercury El to enter thecylindrical central section 55. Upon movement of the buoy to uprightposition the mercury 51 will enter the space 55 and complete the circuitto light the bulb 29.

The dome shaped lower end 52 of the buoy unit prevents standing the buoyon end during storage or normal handling. This is a protective measureto prevent storing in a position which would cause illumination of thelight and depletion of the battery. At the same time the domed shape ofthe lower end of the buoy has advantages in reduced aerodynamic drag ascompared to a flat ended shape.

From the foregoing description it will be evident that I have provided amarker buoy construction having improvements which provide for increasedefficiency and greater reliability. The method of assembly of thevarious components on an exposed framework or chassis not only reducescost and simplifies the operation of placing the parts in the enclosingcasing but allow effective inspection to determine that all parts areproperly assembled and sealed to assure reliable operation. The use ofmy special switch construction for the purpose of lighting the light ina positive fashion provides for further reliability of the operation ofthe signaling apparatus associated with the marker buoy. The locationand shape of the marker dye unit obviously results in increasedcompactness. The improved latch mechanism assures positive disengagementof the buoy from the craft under conditions of increased pressure abovenormal atmospheric, and its operation may be accurately predetermined.This latch mechanism further includes features which prevent inadvertentoperation, particularly with respect to sudden changes of atmosphericpressure such as occur in an aircraft during a dive.

I claim:

1. For a marker buoy, an elongated unit enclosing the various componentsincluding an automatically operated light, a buoyancy chamber, and anautomatic release latch, means for operating said latch including apiston, a piston rod attached to said piston, a chamber at one side ofsaid piston through which said piston rod passes, a sleeve seal betweensaid piston rod and said chamber, and a positive seal around saidpiston.

2. A buoy for marking the location of sunken craft having a releasableunit and a crade for supporting said releasable unit, said cradle beingarranged for attachment to the craft, a latch for connecting said buoyto said cradle, automatic releasingmeans for said latch including adevice having a piston and cylinder, a piston rod extending through oneend of said cylinder, a sleeve-type seal at the point where said pistonrod emerges from said cylinder, and positive pressure seal betweenopposite sides of said piston.

3. A marker buoy having pressure actuated means for automaticallyreleasing the buoy from a sunken craft, said means including latchparts, a cylindrical piston chamber having a Wall at one end, a pistonin said chamber, a piston rod attached to said piston, an opening insaid wall through which said rod projects, a cylindrical nipple on theexterior of said wall, a latch actuating element attached to the end ofsaid rod, said element having a cylindrical external portion thediameter of which is the same as the diameter of the cylindrical nipple,a tightly fitting flexible sleeve engaging said nipple and thecylindrical portion of said element to provide a positive seal at theoutlet of the piston rod from the chamber.

4. A marker buoy having pressure actuated means for automaticallyreleasing the buoy from a sunken craft, said means including latchparts, a cylindrical piston chamber having a Wall at one end, a pistonin said chamber, a piston rod attached to said piston, an opening insaid wall through which said rod projects, a cylindrical nipple on theexterior of said wall, a latch actuating element attached to the end ofsaid rod, said element having a cylindrical external portion thediameter of which is the same as the diameter of the cylindrical nipple,a tightly fit- '8 ting flexible sleeve engaging said nipple and thecylindrical portion of said element to provide a pressure seal at theoutlet of the piston rod from the chamber, a positive seal between thepressure side of said piston and said chamber including a flexiblediaphragm covering said pisten, the edges of said diaphragm beingsealed.

5. For a buoy adapted to mark the location of sunken craft, a buoyancychamber, a pressure actuated latch mechanism for releasing said buoyfrom the craft, said latch mechanism including a cylinder, a piston insaid cylinder, a piston rod projecting from said cylinder, means forproviding a pressure seal between said piston rod and said cylinder,means for providing a positive diaphragm seal between opposite sides ofsaid piston, and a sealed interconnecting passage between said cylinderand said buoyancy chamber.

6. A buoy for marking the location of sunken craft including areleasable latch mechanism for automatically disengaging said buoy froma craft upon submergence, said mechanism including an arc-shaped memberhaving a latch projection thereon, a movable piston, means interconnecting said piston and said latch including a rod elementtelescopically attached to said arc-shaped member.

7. A marker buoy having a pressure actuated device for automaticallyreleasing the buoy from a sunken craft, said device including latchparts, a cylindrical piston chamber, a piston in said chamber,interconnecting mechanism between said piston and said latch parts, aseal between said piston and said chamber, said seal being in the formof a cylindrical pocket of flexible material, the closed end of saidcylindrical pocket being arranged to contact the surface of said piston,the other end of said seal being attached at one end of said cylindricalchamber, therein providing a positive seal between said piston and saidcylindrical chamber while permitting extended motion of the pistontherein.

8. A buoy for marking the location of a sunken craft having a pressureactuated release mechanism for disconnecting said buoy from the craft,said release mechanism incorporating a camshaped latch member having acurved surface, a buoy part which the curved surface of said membercontacts, a piston device, interconnections between said piston deviceand said camsliaped member which produce rolling movement of saidcam-member on said buoy part upon movement of said piston to causerelease of said buoy when said piston device is moved.

9. A marker buoy having a releasable connection for fastening to acraft, a release device actuable by hydrostatic pressure, said releasedevice having a piston member, a piston rod, a'pair of toggle linksconnected to said piston rod by a common pivot, a latch member at theend of each toggle member incorporating a curved portion having aprojection thereon, a reaction part in contact with said curved portion,movement of said piston member thus causing said curved portion to rollupon said reaction part to cause release of said latch members.

10. A buoy for marking the location of sunken craft having a pressureactuated release mechanism for disconnecting said buoy from the craft,said release mechanism including a part connected to the craft andhaving a pair of apertures therein, a pair of toggle members, a pair oflatch members attached thereto, each latch member including a portionhaving an arcuate shape,

a rigid part against which the arcuate portion reacts, a cylinder havinga piston supported therein for longitudinal movement, said piston beingconnected to said toggle members to provide for rotation of said arcuateportion to a position which positively withdraws said latch members fromthe apertures.

11. A buoy device for marking the location ofsunken craft adapted to bereleasably fastened to a craft, latch mechanism for disconnecting thebuoy device from the craft including an anchor plate having an aperturetherein, an areshaped member having a projection for engaging in saidaperture, a rigid part against which said arc-shaped member reacts, acylinder with a piston movable therein, said piston havinginterconnections with said arc-shaped member to cause it to move whensaid piston moves, movement of said arc-shaped member on said rigid partcausing withdrawal of said projection from the aperture.

B. CURTIS GRIEB.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 409,780 Flad Aug. 27, 1889806,730 Zoll Dec. 5, 1905 2,190,531 Kaboskey et a1 Feb. 13, 1940 102,352,226 Ronning June 2'7, 1944 2,355,013 Rochestie Aug. 1. 19442,357,417 Marple Sept. 5, 1944 2,396,960 Marple Mar. 19, 1946 2,397,995Wikstrom Apr. 9, 1946 15 2,404,681 Baack July 23, 1946 2,418,397 Collyeret a1. Apr. 1, 1947 2,451,107 McCabe Oct. '12, 1948 FOREIGN PATENTS 20Number Country Date 25,670 Great Britain of 1913 213,298 Great BritainApr. 10, 1924

